OpenMV 目前并没有resize的功能，你可以在sensor里直接设置图像大小

你不是在所有的sensor设置完之后添加的，你是在中间添加的。

可以添加SCALE_ASPECT_IGNORE

import sensor
import display
import image

sensor.reset()
sensor.set_pixformat(sensor.RGB565)
sensor.set_framesize(sensor.QVGA)
lcd = display.SPIDisplay()

while True:
    lcd.write(sensor.snapshot(), hint=image.SCALE_ASPECT_IGNORE)

硬件是什么？具体代码是什么？固件版本是什么？sensor模组是什么？

这个是调用sensor芯片的isp，对于ov7725：
https://github.com/openmv/openmv/blob/58e89f124ad327ffbd7bf12f0550e913f50646b2/src/omv/sensors/ov7725.c#L583

sensor.set_pixformat(sensor.JPEG)
#FHD 1920x1080 (only for the OV5640 sensor)
sensor.set_framesize(sensor.FHD)

我运行下面的代码很正常，我看到你的尺寸可能不对，应该是QQVGA2保存成bmp

import sensor, image, lcd

sensor.reset() # Initialize the camera sensor.
sensor.set_pixformat(sensor.RGB565) # or sensor.GRAYSCALE
sensor.set_framesize(sensor.QQVGA2) # Special 128x160 framesize for LCD Shield.
lcd.init() # Initialize the lcd screen.

sensor.snapshot().save("test.bmp")
img = image.Image("test.bmp",copy_to_fb=True)
lcd.display(img) # Take a picture and display the image.

import sensor, image, time

sensor.reset()                      # Reset and initialize the sensor.
sensor.set_pixformat(sensor.GRAYSCALE) # Set pixel format to RGB565 (or GRAYSCALE)
sensor.set_framesize(sensor.QQVGA)   # Set frame size to QVGA (320x240)
sensor.skip_frames(time = 2000)     # Wait for settings take effect.
sensor.set_auto_whitebal(False)
clock = time.clock()                # Create a clock object to track the FPS.

clock.tick()# Update the FPS clock.
img = sensor.snapshot().mean(1)
template = image.Image("/template.bmp")
sensor.skip_frames(time = 2000)
diff = img.difference(template)

在RGB565格式时是可以用的

import sensor
import time
import mjpeg
import machine

sensor.reset()  # Reset and initialize the sensor.
sensor.set_pixformat(sensor.RGB565)  # Set pixel format to RGB565 (or GRAYSCALE)
sensor.set_framesize(sensor.QVGA)  # Set frame size to QVGA (320x240)
sensor.skip_frames(time=2000)  # Wait for settings take effect.

led = machine.LED("LED_RED")

while True:
    
    led.on()
    m = mjpeg.Mjpeg("example.mjpeg")
    
    clock = time.clock()  # Create a clock object to track the FPS.
    for i in range(5*60*30):
        clock.tick()
        m.add_frame(sensor.snapshot())
        print(clock.fps())
    
    m.close(clock.fps())
    led.off()
    
    print("saved")

https://docs.singtown.com/micropython/zh/latest/openmvcam/library/omv.image.html#image.to_grayscale

不更改sensor，直接把彩色的图片转为灰度图。